When a person is searching for keys that are in a container with many other items, it may be awkward and time consuming to find them. This is especially common when the keys are in a crowded purse, and the person needs to find the keys in a hurry.
U.S. Pat. No. 6,601,967 issued Aug. 5, 2003 to Zeller discloses a battery-powered flashlight with key holder. The light is actuated when the user rotates a knob. This is only useful after the user has found the key holder.
U.S. Pat. No. 5,400,232 issued Mar. 21, 1995 to Wong, and U.S. Pat. No. 5,465,197 issued Nov. 7, 1995 to Chien disclose vibration flashlights with a spring that at times closes a battery and light emitting diode circuit when vibrated. They are directed to attachment to clothing, shoes, etc. to make the wearer visible while active.
There are dice in the prior art that emit flashing light only when struck vigorously such as by throwing against a surface.
It would be useful to provide a key holder with a self-contained battery that would light up in a cluttered purse only when the purse were shaken.